i rooted while on stock 2.1 and did not have to reactivate. and even if you did have to all you have to do is dial *228 it's really not hard at all. but no if you go to droid-life.com and under the video section there will be a video on how to flash sprecovery onto stock 2.1 and then install a custom rom using sprecovery which will give you root access
I think clarification by "reactivate" is needed. I went ahead and rooted, and the only reactivation that was required was dialing *228. I thought you guys meant that you had to completely reactivate the phone, such as re-entering the ESN number, etc.
Yep and the Droid pretty much does it for you (dials *228). I liked some of the functionality some of the ROMs gave me but I found them laggy or slow to respond. I just moved back to a stock 2.1 myself with root. I like the speed even with using GDE as a home replacement.